This is a good question. There are a few points that can be made.
First, we need to consider the historical context of the movie and book. When we do this, we realize that the story takes place during the 1920 in a context of great wealth. Under closer scrutiny, there is much decadence and waste. More specifically, there is little morality. The appetites of people control them.
Second, from the first point, we can say that there is an absence of traditional morality and religion in a sense. However, there is one great religious symbolism in the of eyes of T.J. Eckleburg. These eyes look over the vast wasteland of immorality. The point might be that the judgment of God is what is taken place. Just like the book of Romans in the New Testament states: "God gave them over to their own sinful desires."